You misunderstand me. I’m fine with disagreeing with a character or saying he/she/it is not interesting (as I’ve done). I’m against directly insulting and criticizing the actor/actress for portraying such character or stating a dissatisfaction.
If John Said I wish I had more scenes with Rose, I would disagree but it’s his right to make is point. If Adam Driver said I wish my character was more powerful and won the last battle, it might not make narrative sense but he is right to say that. To attack the actors for doing their job is deplorable.
Then I apologise and totally agree with your sentiment on it